"Different forms of tourism, especially ecotourism, if managed in a sustainable manner can represent a valuable economic opportunity for local and indigenous populations and their cultures and for the conservation and sustainable use of nature for future generations, and can be a leading source of revenues for protected areas" (UNEP, 2002 In. STRONZA; DURHAM, 2008).

"Unlike other ‘green’ and socially responsible certification programmes for a single product – wood, bananas, coffee, aquarium fish – where the chain of custody can be fairly easily established from the point of origin to wholesalers, retailers and the consumer, tourism is both multifaceted and nonlinear, and involves a wide variety of both services and products" (STRONZA; DURHAM, 2008).